Sealed electrical circuit component



United States Patent Vincent J. Alessi Playa Del Rey, Calif. (83S Seagull Lane Apt. C-212, Newport Beach, CA 92660) 798,265

Feb. 5, 1969 Dec. 22, 1970 Continuation of Ser. No. 624,941, Mar. 21, 1967, now abandoned, which is a division of Ser. No. 371,414, June 1,1964, now

Pat. No. 3,365,284.

Inventor Appl. No. Filed Patented SEALED ELECTRICAL CIRCUIT COMPONENT 3 Claims, 11 Drawing Figs.

[1.8. CI .3 317/234, 317/235 Int. Cl H0111/14 HOll/l/IO Field of Search 317/234, 3.1, 3, 234-31, 4, 235

References Cited UNITED STATES PATENTS 8/1962 Stump Texas Instruments Bulletin No. DL-S 633424, January 1963,p.819

Primary Examiner-John W. I-luckert Assistant ExaminerR. F. Polissack Attorney-I-Iarris, Kiech, Russell & Kern ABSTRACT: An electrical circuit component such as a solid state diode comprising a circuit element such as a chip having a pair of terminal faces with a wire lead butt joined to each terminal face and with a tubular glass sleeve encasing the element and lead ends and fused to the [lead ends.

PATENTED utczelam 3.549.959

SHEET 1 OF 2 INVENTOR. V/A/cEA/T J. ALESS/ av ms ATTORNEYS H4220; Maw, RUSSELL & KER/v PATENTEU 119222 mm same or 2 R: mwfi m/um V WMW A s mm mm V 1 0H 21 n Z 1 1 I 2 F HARE/:3, A/IECH, RUSSELL & Ksww sion of my then copending application entitled Diode and the Like and Method of and Apparatus for Making the Same, Ser. No. 371,414, filed June 1, 1964, .now US. Pat. No. 3,365,284.

This invention relates to new circuit components and is par ticularly directed to a variety of sealed circuit components including diodes, resistors, rectifiers, capacitors, transducer elements, coils, switches and relays, radiation detectors, and photoelectric and photovoltaic devices. The invention will be described herein as applied to conventional solid state diodes but its application to other circuit elements will be readily understood.

It is an object of the invention to provide a new and improved sealed electrical circuit component which is simple in design, incorporates few parts, is inexpensive and rugged.

It is a specific object of the invention to provide a new and improved circuit component such as a diode or the like and comprising a circuit element having a pair of terminal faces with a wire lead butt-joined to each terminal face and with a tubular glass sleeve encasing the circuit element and lead ends and fused to the lead ends. A particular advantage of this construction is the utilization of simple wire leads which are directly connected to the circuit element and which do not require any prior terminal forming operation or any intermediary terminal structures.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. The drawings merely show and the description merely describes preferred embodiments of the present invention which are given by way of illustration or example.

In the drawings:

FIG. 1 is a perspective view of a preferred form of apparatus for performing the method of the invention;

FIGS. 2 and 3 illustrate two steps in the assembly of a circuit component;

FIG. 4 illustrates a completed circuit component;

FIG. 5 is a perspective view of an alternative form of ap paratus for performing the method of the invention;

FIGS. 6--10 illustrate five steps in the process of forming the circuit component by the apparatus of FIG. 5; and

FIG. 11 illustrates a completed circuit component which may be identical to the component of FIG. 4.

The circuit component of FIG. 4 typically may be a solid state diode comprising a silicon junction dice 20, leads 211, 22 and a glass sleeve 23. The butt ends of the leads 211, 22 are joined by alloying to opposing faces of the dice 20. The glass sleeve 23 is fused to the lead ends to provide a completely hermetically sealed component.

The leads preferably are of metal wire having a temperature coefficient of expansion substantially the same as that of the circuit element and the glass sleeve. Also, the lead material and the glass composition preferably are selected so that the lead-to-silicon dice alloying and the lead-to-sleeve fusing occur at substantially the same temperature permitting the complete joining and sealing operation to be performed at one time. In a typical unit, the wire leads will be a silver clad nickel-iron wire and the glass will be a potash-soda-lead glass, such as Corning G12 (0120), which permit sealing at 850 C. Of course, copper clad nickel-iron wire and other alloys such as dumet wires may be utilized. The particular wire and glass utilized in any specific component may be varied to suit various applications, keeping in mind the criteria set out above.

Referring now to the apparatus of FIG. 1, a silicon dice is fed from a vibratory feeder 25 through a metering eseapement 26 to the assembly position where it may rest in a groove in an arm 27. A sleeve 23 is fed from another vibratory feeder 2% through a metering eseapement 29 to rest on another arm 30.

A lead wire from a spool 32 is advanced by a chuck 33 in a wire drive mechanism 34 through a wire straightener 35 to bring the butt end of the lead wire 21 into engagement with the dice 20, as best seen in FIG. 2. Similarly, wire from another spool 38 is fed through a drive mechanism 39 having a chuck db and wire straightener ll, with the lead 22 passing through the sleeve 23 to engage the other face of the dice 20.

The wire feed mechanisms 34, .39 maintain a compressive force on the dice Z0, permitting the arm 27 to be withdrawn to the position of FIG. 11, after which the sleeve 23 is advanced by an arm 43 to overlie the dice and lead ends, as seen in MG. 3.

The temperature of the circuit element, the glass and the ends of the leads is raised to the sealing temperature as by means of a heating coil 15. The wire leads are now cut to the desired length by anvil do and blade 17 and anvil db and blade 49 producing the completed component of FIG. d. The component is now transferred to the ways of a conveyor 50, as by the arm 27.

The wire lead cutting operation is preferably performed so that the coating material on the wire is smeared over the freshly cut butt end to bring this coating material into position for engagement with the next circuit element to be fed into the apparatus, as the alloying operation is best carried out with the silver or copper wire coating material rather than with the wire core material. The degree of smearing occuring during shearing may be varied by controlling the shear blade sharpness and the pressure between the blades.

Completed circuit elements 51, 52 are moved along the conveyor 50 past any desired number of stations where various electrical tests may be performed on the components. At one station, the components may be symbolized by the application of painted or printed markings, depending upon the results of the preceding tests. Finally, the components are directed to a sorter 53 where each component is directed to a particular container 5 1, 55, 56 by means of electrically operated gates, depending upon the characteristics of the specific component as determined by the testing. The components may be stored and shipped in the containers or may be conveyed on to automatic packaging machines for appropriate packaging.

The method and apparatus described above provide a complete and continuous operation for the manufacture of an electrical circuit component without requiring any intermediate storage of subassemblies and without requiring any manual manipulation of the various elements. Of couse, the method itself could be carried out by hand if desired.

An alternative apparatus for the manufacture of the circuit component is shown in FIG. 5. A plurality of lead clamping jaws 70-77 is carried on a work table 78 which is rotated by various indexing means, such as a pawl '79 and rachet 80 as illustrated. With this arrangement, a number of components can be in process of assembly at the same time, with various steps performed at different positions around the work table.

An assembly operation is started by feeding wire upward from a spool 81 into the jaw '70, the wire feeding being performed by a chuck 82 in a wire feed mechanism 83 which includes a wire straightener M. This wire, which will function as the lead 21, projects upward from the jaw 70, as seen in FIG. 6. The wire is now out as by a shear 85 and the work table may now be rotated to bring the lead 211 to the position shown with the chuck 71 A glass sleeve 23 is fed down onto the upwardly projecting end of the lead 21 from a feeder 86 (H6. 7 Next the silicon dice 20 is fed down into the sleeve from another feeder 87 (FIG. 8).

At the position of the chuck 73, the other lead wire is fed downward from a spool 90 to a wire drive mechanism 91 and into the sleeve 23 engaging the upper terminal surface of the silicon dice. The assembly is heated as by an induction coil 92 and the upper lead wire is cut by shear 93 to produce the completed component as seen in H0. l0.

In an alternative arrangement, the upper wire may be cut and the assembly may then be transferred to the next position for heating and sealing. The component is finally transferred to the position of the jaw 77' and is released onto a conveyor 95 for testing and further handling as in the apparatus of FIG. 1.

It will be readily understood that the invention is not limited to solid state diodes and that the method and apparatus described herein are equally suitable for the manufacture of 5 other electrical circuit components utilizing other electrical elements since the characteristics of the element itself are not a factor in the operations. The only requirement on the circuit element itself is that it have terminal faces to which the wire leads can be joined by heating in an alloying or soldering operation.

Although exemplary embodiments of the invention has been disclosed and discussed, it will be understood that other applications of the invention are possible and that the embodiments disclosed may be subjected to various changes, modifications and substitutions without necessarily departing from the spirit of the invention.

lclaim:

1. An electrical circuit component consisting of a circuit element having at its ends opposed terminal faces and a continuous, unitary and uniform-diameter wire lead of substantially the same diameter as said circuit element butt-joined directly to each terminal face with no intermediary terminal structure, and a glass sleeve having an inside diameter substantially equal to the diameter of said wire leads and said circuit element encasing the element and lead ends and fused to the lead ends, and each of said unitary wire leads extending from said sleeve a distance many times the diameter of said wire leads to provide for installation in an electrical circuit, said circuit element, said wire leads and said sleeve all having substantially the same temperature coefficient of expansion, and said circuit element and said wire leads forming a continuous and uninterrupted structure, free from voids, throughout the entire interior of said sleeve.

2. An electrical circuit component consisting of a circuit element having at its ends opposed terminal faces and continuous, unitary and uniform-diameter wire leads, each wire lead consisting of a nickel-iron core having a coating of :a material selected from the group consisting of silver, copper, and silver-copper mixtures, and each wire lead having a butt end covered with the coating metal and joined directly to a terminal face, and a glass sleeve encasing the element and lead ends and fused to the lead ends, the finished length of each of said unitary wire leads being manytimes the diameter thereof for installation in an electrical circuit, said circuit element having substantially the same diameter as said wire leads and the inside diameter of said sleeve being substantially the same as the diameter of said wire leads andcircuit element, said circuit element, said wire leads and said sleeve all having substantially the same temperature coefficient of expansion, and said circuit element and said wire leads forming a continuous and uninterrupted structure, free from voids, throughout the entire interior of said sleeve.

3. A diode consisting of a solid state junction chip and continuous, unitary and uniform-diameter wire leads butt-joined directly to opposite faces thereof, and a glass sleeve encasing the chip and lead ends and fused to the lead ends, and the finished length of each of said unitary wire leads being large as compared to the diameter thereof for installation in an electrical circuit, the chip being of substantially the same diameter as said wire leads and the inside diameter of said sleeve being substantially the same as the diameter of said wire leads and chip, said chip, said wire leads and said sleeve all having substantially the same temperature coefficient of expansion, and said chip and said wire leads forming a continuous and uninterrupted structure, free from voids, throughout the entire interior of said sleeve. 

